First - not an expert in the trade but have installed my two mini splits myself. You should have a set of gauges between your vacuum pump and mini split. Running the vacuum for the extended time ensures a complete vacuum and removes moisture. You should close the valve on the gauge leading to...
I made a dust skirt for the Home Depot grinder out of a 4" wide strip of upholstery vinyl. Wrapped it around the base with the bottom edge just hitting the floor. Made a lot of 1/4" slits spaced about 1/4" apart all the way round. This worked to get my garage ground for epoxy.
Call Legacy, they were wonderful to work with and will answer all of your questions. My understanding is hd = heavy duty, sd = standard duty.
I used the HD and added polyurethane clear with non-slip on top. Absolutely love my floor!
I purchased the first of my two units online from Comfort Up. Great price, excellent communication, and fast free shipping. I chose to risk the warranty for a DIY install with the help from my neighbor who is a retired HVAC contractor. Professional install was more $ than the unit. Been working...